Small, handheld computing devices have been steadily growing in popularity in recent years. The devices go by different names, including palmtops, pocket computers, personal digital assistants, personal organizers, and the like. In this disclosure, this class of computing devices is generally referred to as "handheld personal computers", "handheld PCs", or "H/PCs".
H/PCs are small, pocket-sized devices having an LCD (liquid crystal display) with a touch-sensitive screen, a stylus to enter data through the screen, and an input device such as a keypad or miniature QWERTY keyboard. H/PCs have a microprocessor, memory, and are capable of running an operating system and one or more applications on the operating system. Microsoft Corporation recently released the Windows.RTM. CE operating system for use on H/PCs, which is a scaled-down version of its popular Windows.RTM. operating systems manufactured for personal computers.
One of the most desirable characteristics of H/PCs is their portability. The compact, portable H/PCs provide a user with real computer-like applications--such as email, PIM (personal information management), Internet browser, spreadsheet, word processing. A traveling user can receive email messages, schedule meetings or appointments, and browse the Internet from the H/PC.
Chief among the design compromises is an undersized display. Screen space is very limited. Traditional user interface techniques which users are accustomed to on desktop computers are not available for H/PC displays due to the limited size. Additionally, the screen must be efficiently utilized to enable effective data input from the stylus.
In view of this design constraint, it would be advantageous to develop user interfaces that can be effectively employed on the miniaturized screen of a handheld computing device.